Functions of nonsuicidal self-injurious behavior in Russian patients with suicidal ideation

Introduction Nonsuicidal self-injurious behavior (NSSI) is an important risk factor for future suicide attempts. Previous research has identified a number of motivations for engaging in NSSI. The aim of the present study was to translate the Inventory of Statements About Self-Injury (ISAS) into Russian and then to evaluate its psychometric properties in a sample of patients with non-psychotic mental disorders and suicidal ideation (SI). Other aims were to determine the prevalence of specific NSSI functions in this population and to assess the relationship between different NSSI functions and clinical and psychological parameters. Participants and methods The study was conducted at the largest center for non-psychotic mental disorders in Moscow. All admitted patients with both NSSI and SI completed the Russian version of the ISAS-II, underwent the Self-Injurious Thoughts and Behaviors Interview, and completed the Personality Inventory for DSM-5 and ICD-11 Brief Form Plus-Modified, the Beck Depression Inventory, and the State–Trait Anxiety Inventory. Results A total of 614 patients were included in the study. 543 (88.4%) patients were assigned female at birth with a mean age of 24.86 (7.86) years. Factor analysis supported a two-factor structure (Intrapersonal and Interpersonal) of the Russian version of the ISAS-II, but in contrast to the original study, the “Marking distress” function loaded more strongly on the Interpersonal factor. In people with non-psychotic mental disorders and SI, Interpersonal functions of NSSI are associated with more severe depressive symptoms (r = 0.34), 12 months history of NSSI (r = 0.30), higher number of NSSI methods (r = 0.41), likelihood of future NSSI (r = 0.35) and psychoticism (r = 0.32). Conclusion The Russian version of the ISAS-II is a valid and reliable instrument for assessing NSSI functions in a population at high risk for suicide attempts. Interpersonal functions are associated with a number of unpleasant clinical and psychological features.


Introduction
Suicide remains one of the leading causes of preventable death, particularly among young adults (1).The death rate from suicide has not shown a significant decline in recent decades (2), comparable to that observed for many other causes of premature death (3,4).Despite the many studies carried out each year in this area, the problem remains unresolved and it is appropriate to continue the search for modified predictors of suicide.
Recent studies have identified nonsuicidal self-injury (NSSI) as a highly significant risk factor for future fatal and non-fatal suicide attempts (5)(6)(7).People with mental disorders who also have suicidal ideation and NSSI are clearly a group at highest risk of attempting suicide.At the same time NSSI is highly prevalent both in the general population (8) and particularly among people with mental disorders (9,10) and only a minority of them attempt suicide.Therefore, research into the characteristics of NSSI that distinguish those at high risk of suicide is warranted.Over the last decade, the number of studies on NSSI has increased, but the data obtained vary considerably depending on the methods used by the authors (11,12).A set of instruments that are freely accessible, available in many languages and validated in different countries is a prerequisite for conducting comprehensive comparative studies on NSSI and suicidal behavior.
To date, none of the self-report instruments used by researchers worldwide to assess parameters associated with NSSI (13) has been validated in the Russian language.The lack of a tool to assess the functioning of NSSI hinders progress in the development of appropriate suicide prevention programs in Russia.It's worth noting that suicide remains a major public health problem in the Russian Federation as the country's suicide mortality rate has exceeded the European average for several decades (14).These data contrast with the relatively small number of published papers on suicidal behavior (15), and very few of these have considered NSSI as a potential risk factor for suicidality (16)(17)(18).Among the many reasons for ignoring this very important issue, the lack of validated Russian-language instruments for NSSI studies may be one of the most important.
Another benefit of validating the instrument for assessing NSSI functions is the development of more precise treatment strategies for individuals with specific NSSI motives.For example, programs aimed at increasing emotional tolerance (e.g., Dialectical Behavior Therapy) may be recommended for patients for whom affect regulation is the dominant motive for NSSI, whereas programs aimed at improving communication skills and family therapy may be recommended for those for whom distress communication is the primary function (19)(20)(21).
The Inventory of Statements About Self-Injury (ISAS) (22,23) is a freely available tool that provides information about NSSI parameters such as type of NSSI, age of onset, date of last NSSI, experience of physical pain, willingness to stop self-harm (ISAS-I), and key functions of NSSI (ISAS-II).The instrument has been validated in many languages including Serbian (24), Spanish (25), Hungarian (26), Persian (27), Korean (28), Turkish (29), Urdu (30), and Swedish (31), and is currently in active use worldwide.Most of the translated versions of this instrument showed good internal consistency and the 2-factor structure of the ISAS-II (intrapersonal and interpersonal factors), which is consistent with the results of the original study.For example, in a Turkish study factor analysis of the functions scale confirmed the good fit of the original 2-dimensional model (RMSEA = 0.08 (0.07-0.09);CFI = 0.97; NFI = 0.97) (29).Cronbach's alpha was 0.92 for the Korean version of the ISAS-II, indicating excellent internal consistency reliability (28).The test-retest reliability of the instrument was also found to be good (32).
Previous studies that using the ISAS-II have found that certain NSSI motives are more strongly associated with various adverse outcomes than others.For example, Reinhardt et al. (33) found that intrapersonal, but not interpersonal NSSI functions were associated with indicators of NSSI severity (current and recurrent NSSI, versatility of methods).In addition, a number of psychopathological features (co-occurring mental disorders, presence of a mood disorder, internalizing symptoms of mental illness, and self-critical rumination) were associated with engagement in NSSI for intrapersonal reasons.Thus, studies using the ISAS to assess the functions of NSSI may provide insight into the place of different subtypes of NSSI within the psychopathological taxonomy.
However, even though the ISAS is not a diagnostic tool and does not require a cut-off point, the use of simply translated versions of the instrument without studying its psychometric properties (31,34) should not be considered good practice.For example, even for instruments with fewer questions, inconsistencies in the factor structure between the original and Russian-language versions have been reported (35,36).Moreover, in the Iranian study (37), the EFA showed a single-factor solution that provided an adequate fit in the subsequent confirmatory factor analysis (CFA).In addition, a Japanese study (38) reported a three-factor structure of the instrument: "Distress coping functions, " "Interpersonal influence functions, " and "Identity maintenance functions." Also, the study conducted in a Mexican student population (39) found 7 interpretable factors ("Self-regulation, " "Revenge, " "Sensation seeking/toughness, " "Avoiding suicide, " "Marking distress, " "Self-determination and numbness"), 5 more than the original version of the ISAS-II.These data support the need for a psychometric study of the Russian version of the ISAS-II prior to its use.
The primary aim of the study was to translate the ISAS-II into Russian language and then to examine its psychometric properties in a sample of Russian-speaking patients with non-psychotic mental disorders and suicidal ideation.It seems crucial to understand the characteristics of the instrument in this special population, which is characterized by an enormously high risk of suicide attempts.
The next aims of the study were to obtain data on the prevalence of various NSSI functions in a consecutive sample of Russian patients with non-psychotic mental disorders and suicidal ideation, and to assess the relationship between various NSSI functions and clinical (diagnosis, depression and anxiety levels, self-harm thoughts and behaviors) and psychological (personality traits) characteristics.
Patients with primary psychotic disorders were not included in this study because we believe that a separate study of NSSI functions in these patients is warranted.This is because many key parameters for understanding these patients are not applicable to people with non-psychotic mental disorders (e.g., duration of untreated psychotic symptoms, impaired insight, and negative symptoms).Each of these parameters could potentially affect the motivation for NSSI, and we decided not to include people with primary psychotic disorders in the study.The study was conducted at the Department of Suicide Research and Prevention at the Moscow Research and Clinical Center for Neuropsychiatry.The Center specializes in the treatment of patients with non-psychotic mental disorders.The study cohort is represented by patients with SI and NSSI aged >18 years and older, identified from a consecutive cohort of patients with non-psychotic mental disorders and suicidal ideation.Patients with primary psychotic disorders, current substance use disorders, cognitive deficits below the level of comprehension on self-report scales and interviewer questions were excluded from the study.
All patients are screened on admission for lifetime SI, suicide attempts (SA), and NSSI.The screening includes the first items in the relevant sections of the Self-Injurious Thoughts and Behaviors Interview (SITBI) -"Have you ever had thoughts of killing yourself?""Have you ever actually made a plan to kill yourself?"and "Have you ever actually engaged in NSSI?"All patients are then seen by an experienced psychiatrist to confirm the diagnosis of a non-psychotic mental disorder according to ICD-10 criteria.
All eligible patients then completed the study questionnaires and were interviewed by the investigator to collect basic sociodemographic information and data on self-injurious thoughts and behaviors.The first patient was enrolled in January 2018 and the last in December 2019.

Measures
The Inventory of Statements about Self-Injury-II (ISAS-II) consists of 39 items with responses rated on a 3-point Likert scale from 0 (not relevant) to 3 (very relevant).The list of items begins with an opening statement: "When I self-harm, I am…" According to the authors of the original study, the ISAS-II has two higher-order functions (Interpersonal and Intrapersonal) and 13 lower-order facets.The Intrapersonal function in the original ISAS-II version consists of motives for NSSI such as "Affect regulation" (… releasing emotional pressure that has built up inside of me), "Anti-dissociation/feelinggeneration" (… causing pain so I will stop feeling numb), "Antisuicide" (… avoiding the impulse to attempt suicide), "Marking distress" (… creating a physical sign that I feel awful), "Selfpunishment" (… punishing myself) and the Interpersonal function includes "Autonomy" (… demonstrating that I do not need to rely on others for help), "Interpersonal boundaries" (… demonstrating that I am separate from other people), "Interpersonal influence" (… letting others know the extent of my emotional pain), "Peer bonding" (… bonding with peers), "Revenge" (… getting back at someone), "Selfcare" (… creating a physical injury that is easier to care for than my emotional distress), "Sensation seeking" (… doing something to generate excitement or exhilaration) and "Toughness" (… seeing if I can stand the pain).The Cronbach's alpha coefficient of the original ISAS-II version indicated good internal consistency for the interpersonal (0.88) and intrapersonal (0.80) factors (23).
With the permission of the author of the instrument (prof.ED Klonsky), the Russian version of the ISAS-II (Appendix 1) was developed using the back-translation method, which is recommended as a first step in cross-cultural adaptation of instruments.The original version of the ISAS-II was translated from Russian by two native Russian psychiatrists, both of whom were fluent in English.The Russian version of the tool was then back-translated into English by another bilingual translator on the research team to confirm that the translation was consistent with the wording of the original scale.Finally, the Russian version was compared with the original version by an Englishspeaking consensus committee of clinicians.If there were discrepancies between the two versions, individual items underwent additional rounds of back-translation until they were deemed satisfactory.The developed version of the tool was tested on 16 patients with NSSI (8 females).In their feedback, none of the participants reported any difficulties in understanding the instructions for the tool or the meaning of the items.This version of the ISAS-II was later used in our study.
The Self-Injurious Thoughts and Behaviors Interview (SITBI) is a structured clinical diagnostic interview consisting of the following blocks: suicidal thoughts, suicide plans, suicide attempts, suicidal gestures, non-suicidal self-injurious thoughts and non-suicidal selfinjurious behaviors (40).Each block contains up to 30 questions on prevalence, frequency, and contextual factors.The Russian version of the SITBI is mainly used for scientific purposes (17, 41), but in some clinical centers it is also used in routine clinical practice.For the purposes of this study, we used the SITBI questions on prevalence and age of onset of SI, SA, and NSSI, as well as items on methods of self-injury and questions assessing descriptive and contextual factors of NSSI.
The Personality Inventory for DSM-5 and ICD-11 Brief Form Plus-Modified (PID5BF + M) is part of the DSM-5 family of personality trait questionnaires (42,43).The PID5BF + M was proposed by Bach et al. (44) and consists of 36 questions rated on a 4-point Likert scale from 0 (very untrue or often untrue) to 3 (very true or often true).The questionnaire assesses 6 domains, including 3 facets, each consisting of two questions: Negative Affectivity (emotional lability, anxiousness, and separation insecurity), Detachment (withdrawal, anhedonia, intimacy avoidance), Antagonism/Dissociality (manipulativeness, deceitfulness, grandiosity), Disinhibition (impulsivity, irresponsibility, distractibility), Anankastia (rigidity, perfectionism, and orderliness), and Psychoticism (unusual beliefs, perceptual dysregulation, eccentricity).The instrument showed good internal consistency (McDonald's omega coefficients ranged from 0.83 to 0.90) and its factor structure was fully consistent with the results of the study of the original version of the questionnaire (45).The Beck's Depression Inventory (BDI) was developed to assess the severity of depressive symptoms (46).It consists of 21 items, each rated on a 4-point Likert scale from 0 to 3. The psychometric properties of the Russian version of the BDI have been previously evaluated, with Cronbach's alpha coefficients of 0.86 (47).
The State-Trait Anxiety Inventory (STAI) consists of two parts assessing state (STAI-S) and trait (STAI-T) anxiety (48).Each part contains 20 items and is scored on a 4-point Likert scale ranging from 1 (not at all) to 4 (very much so).The questionnaire has previously been validated in Russian by Khanin (49), with Cronbach's alpha of 0.89 and 0.85 for the state and trait anxiety modules, respectively (50).

Statistical analysis
Categorical variables are presented as frequencies (%) and continuous variables as arithmetic means (standard deviation).
Factor structure was assessed using exploratory factor analysis (EFA) with standard geomin (oblique) rotation and the weighted least square mean and variance adjusted (WLSMV) estimator.WLSMV is a robust estimator suitable for responses with four or fewer response categories and can be corrected for non-normality in the data set (51)(52)(53).Kaiser-Meyer-Olkin (KMO) and Bartlett's sphericity tests were used to assess the suitability of the data for EFA.
The internal consistency of the questionnaire was assessed using McDonald's omega scores (ω) (53).Average inter-item correlations of the NSSI functions were also calculated to assess item homogeneity (54).
Correlational analysis was used to assess the relationship between NSSI functions and sociodemographic and clinical variables.Correlations between inter/intrapersonal functions and binary variables (age, mental disorder diagnoses, lifetime and 12 months suicide attempts, and 12 months NSSI and NSSI medical treatment) were assessed using biserial correlations.Polyserial correlations were used to examine associations between NSSI functions and ordinal variables (SITBI items 153-162, 165-169) and Pearson's correlations for continuous variables.

Sample characteristics
Of the 3,644 patients screened, 655 (18.0%) were positive for lifetime SI and NSSI.Forty-one patients refused to participate in the study or completed the ISAS-II incorrectly.Thus, 614 patients were included in the final study calculation, of which 14 refused to undergo the SITBI but did not object to the use of their completed questionnaire data in the calculation.Data from these patients were therefore excluded from the analysis of the relationship between NSSI function and the SITBI variables.
Clinical and demographic variables are presented in Table 1.The majority of patients were assigned female at birth (N = 543; 88.4%) with a mean age of 24.86 (SD 7.86; range 18-72) years.Fifty-one patients (8.3%) had an alternative gender identity (those with a non-binary gender identity (e.g., gender fluid, agender, and bigender) and those receiving gender affirming care).

Factor structure of the questionnaire
The EFA yielded a two-factor solution that accounted for 38.4% of the total variance.Factor 1 had an eigenvalue of 10.1 and included Intrapersonal functions, and Factor 2 had an eigenvalue of 4.9 and included Interpersonal functions.The two factors had an intercorrelation of 0.22.As can be seen in Table 2, 34 of the 39 item loadings were consistent with the loadings reported by Klonsky and Glenn (23).Three items (11, 24, and 37) loaded on the Interpersonal rather than the Intrapersonal factor, and item 17 loaded on the Intrapersonal rather than the Interpersonal factor.Item 7 was cross-loaded on two factors, but both factor loadings were low (0.25).In order to maintain the integrity of functions such as "Sensation Seeking" and "Self-care," it was decided to place items 7, 17 in the original factors.Thus, Intrapersonal functions included functions such as "Affect regulation," "Self-punishment," "Anti-suicide" and "Antidissociation," and interpersonal functions -"Marking distress," "Self-care," "Interpersonal influence," "Toughness," "Sensationseeking," "Interpersonal boundaries," "Autonomy," "Revenge" and "Peer bonding."

Internal consistency of the questionnaire
The McDonald's omega coefficient for the ISAS-II was 0.85, indicating good internal consistency.The internal consistency coefficients for the functions of the NSSI are presented in Table 3.
McDonald's omega coefficients for Intrapersonal and Interpersonal functions were greater than 0.80.The internal consistency of most of the NSSI motives was acceptable (ω ≥ 0.70), except for the coefficients for "Self-Care, " "Sensation seeking, " "Interpersonal boundaries, " and "Peer bonding, " which ranged from 0.55 to 0.70, indicating less adequate reliability.
The average inter-item correlation coefficient for the ISAS-II was 1.51.As shown in Table 3, the average inter-item correlations for the Interpersonal and Intrapersonal functions and most of the subfunctions were within the acceptable range of 0.15-0.50.

Factors related to the interpersonal and intrapersonal functions of NSSI
The results of the correlation analysis are presented in Table 4.A total of Intrapersonal self-injurious motives had significant positive weak correlations with and BDI score (r = 0.34) and negative significant weak correlations with age (r = −0.39).Significant weak positive correlations were found between Intrapersonal NSSI functions and psychoticism.

Sample characteristics
As the presence of NSSI and SI was assessed in all patients admitted to the inpatient unit, we were able to determine the prevalence of combined NSSI+SI in the hospital population of patients with non-psychotic mental disorders, which was 18.0%.Basic socio-demographic and clinical characteristics of the sample are shown in Table 1.The predominance of women in the sample is consistent with data on their greater use of psychiatric care.Recent study has found that over 76% of patients in the Moscow clinic for patients with non-psychotic mental disorders are women (55).On the other hand, the predominance of young people, those assigned female at birth and a significant proportion of participants with alternative gender identities is consistent with findings from studies conducted in other countries (56)(57)(58).
The distribution of diagnoses in the sample reflects the peculiarities of the organization of psychiatric services in the Russian Federation.In Russia, clinics treat patients with so-called non-psychotic mental disorders separately from patients with primary psychotic disorders, patients with mood disorders with psychotic features and patients with addictive or organic psychotic disorders.At the same time, patients with schizotypal and borderline personality disorders, even if they have transient psychotic symptoms, are

Internal consistency and factor structure
The Russian version of the ISAS-II has good overall internal consistency (ω = 0.85), and the omega coefficients for the Intrapersonal (0.83) and Interpersonal (0.85) functions were either greater than 0.80 (Table 3).These data indicate a good internal consistency between these factors and are in line with the results of a study by Klonsky and Glenn (23) (Intrapersonal -0.88 and Interpersonal -0.89) and some other studies (61).Interestingly, the internal consistency of the Intrapersonal factor functions was higher (range 0.71-0.83)than that of some of the Interpersonal factor functions (range 0.53-0.78).At the same time, although most of the NSSI motives had acceptable internal consistency (ω ≥ 0.70), the coefficients for "Self-care, " "Sensation seeking, " "Interpersonal boundaries" and "Peer bonding" ranged between 0.55 and 0.70, indicating less adequate reliability.The correlation between the Intrapersonal and Interpersonal functions in our sample was low (0.22).The average inter-item correlations for the Interpersonal and Intrapersonal functions and most of the subfunctions were within the acceptable range of 0.15-0.50.
An analysis of the distribution of items by factor (Intrapersonal and Interpersonal) in the Russian version of the ISAS-II revealed a number of differences from the original version (Table 2).The main difference between the Russian version of the ISAS-II and the original version of the questionnaire was that all 3 items of the "Marking distress" subscale loaded more strongly on the Interpersonal factor.Previously, a study by Reinhardt et al. (62) found that "Marking distress" on a par with "Interpersonal boundaries, " "Sensation Seeking, " "Toughness" and "Autonomy" motives may have both Intrapersonal and Interpersonal components.In the same study, the "Marking distress" function had a salient loading on the Interpersonal factor in male adolescents.Our results are consistent with the study by Vigfusdottir et al. (63), conducted on a sample of Norwegian students, which also showed that the "Marking distress" function loaded more on the Interpersonal factor, in contrast to the original study by Klonsky and Olino (22).In the Korean study (28), − item 11 of the "Marking distress" function also loaded on interpersonal rather than intrapersonal functions.
Another feature of the Russian version of the ISAS-II was that the item 17 ("Creating a physical injury that is easier to care for than my emotional distress"), which in the original version belonged to the Interpersonal function "Self-care" (self-injuring to create a physical wound that one can care for more easily than one's emotional distress) (23), had a greater load on the Intrapersonal factor.The authors originally expected the "Self-care" function to be theoretically related to the intrapersonal factor, but in the original study this function had a higher load on the Interpersonal (0.41) than on the Intrapersonal factor (0.33) (23).It is interesting to note that in the original study the loading on the Interpersonal factor was only slightly higher than on the Intrapersonal factor.In a more recent study by Klonsky et al. (64), item analysis was performed and showed that item 17 loaded on the Intrapersonal (0.50) rather than the Social factor (0.26), which is fully consistent with our results.In the Russian version of the ISAS-II, the other two items of the "Self-care" function had high loadings on the Interpersonal factor, but the factor loadings were low.The "Self-care" function was also clearly loaded on the Intrapersonal function in the studies by Kortge et al. ( 65), Vigfusdottir et al. (63), and Pérez et al. (25).In the last of the above-mentioned studies (25), the model in which the "Self-care" function was included in the Intrapersonal factor was found to be preferable to the original model in which it was identified as an Interpersonal function.It is also noteworthy that the other "Self-care" function items, although more heavily loaded on the Interpersonal factor, had some of the lowest loadings of all questionnaire items (0.4 for item 4 and 0.35 for item 30).Given the instability of the "self-care" subfunction (both the items within it and the subfunction as a whole) identified in several studies, we believe that developing a revised version of the ISAS based on the experience of the validations may be the best decision.A new version of the instrument should either clarify the wording of the questions or remove this function altogether.
Another ISAS-II item that showed low factor loadings on both factors was item 7 ("Doing something to generate excitement or exhilaration"), which refers to the "Sensation-seeking" function.Previously, the Korean study (28) found that, contrary to the original research, item 7 loaded more on the Intrapersonal than on the Interpersonal function.

NSSI functions in patients with suicidal ideation
In our study, patients practiced in NSSI for both Intrapersonal and Interpersonal motives (Table 3), which is consistent with most studies, but the prevalence differed from that presented in the meta-analysis by Taylor et al. (66).The three most common Intrapersonal NSSI functions in our sample were "Affect regulation" (96.1%), "Self-Punishment" (87.1%), and "Anti-Suicide" (75.9%), and the most common Interpersonal functions were "Marking distress" (78.8%), "Self-care" (68.9%), and "Interpersonal influence" (54.9%).In a meta-analysis by Taylor et al. (66), avoidance or escape from an unwanted internal state was also the

Correlations between NSSI functions and personality traits
We conducted a correlational analysis of Interpersonal and Intrapersonal functions with sociodemographic, clinical and personality profile variables.We also examined correlations between ISAS-II functions and parameters from the SITBI Non-suicidal selfinjury module (items 144-169).We found small positive correlations (0.3-0.5) between Intrapersonal NSSI functions and lower age, higher BDI score, NSSI episode in the past 12 months, higher number of NSSI methods, "mental state at the time" as a cause of NSSI, and selfreported high likelihood of engaging in NSSI in the future.Our findings in the Russian-speaking patients on the relationship between Intrapersonal functions and the less favorable course of NSSI in patients with non-psychotic mental disorders are consistent with the results of studies conducted in other linguistic and cultural samples (67,68).
To the best of the authors' knowledge, no correlational analysis has previously been conducted between DSM-5 personality trait domains and NSSI functions.At the same time, the relationship between NSSI behavior and higher levels of Negative affectivity, Detachment, Antagonism and Psychoticism has been previously reported by researchers (69-73).The Psychoticism domain of the PID-5 includes traits such as Unusual Beliefs & Experiences, Eccentricity, and Perceptual Dysregulation (74).According to Peng et al., patients with depression and NSSI have significantly higher levels of psychoticism than healthy controls and patients with depression alone (73).In addition, regression analysis showed that psychoticism was an independent risk factor for NSSI in depressed patients.These data are supported by the results of the study by Kang et al. (74).In our study, Intrapersonal NSSI functions had the highest correlations with psychoticism (0.32).In our opinion, this may be explained by the fact that psychoticism is associated with a wellknown difficulty in dealing effectively with emotional conflict.For example, a study by Granieri et al. found that two immature defense mechanisms -autistic fantasy and isolation -predicted the PID-5 Psychoticism domain in participants (75).While attempts to cope with the unwanted effects of dissociation are among the most common Intrapersonal motives for NSSI, psychoticism has been repeatedly reported to be associated with a high risk for the development of dissociative phenomena (76).
In our study, NSSI Interpersonal functions had the highest correlations with the Antagonism domain (0.25).An association between NSSI and low agreeableness has also been reported in some previous studies (76)(77)(78).This variable indirectly reflects antagonism, which, according to the authors of the PID-5 (74), includes traits such as Manipulativeness, Deceitfulness and Grandiosity.The relationship found between Interpersonal functions and Antagonism is consistent with the suggestion by some authors that some NSSI behaviors directed at the environment may involve aggressive goals (e.g., "Revenge" motives).
The SITBI questions related to self-harm motives (items 153-156) had the highest correlations with NSSI functions.The results were as expected: Interpersonal functions correlated with "… to communicate with someone else or to get attention?"(0.42) and "… to get out of doing something or to get away from others?" (0.40), and Intrapersonal functions with statements such as "… a way to get rid of bad feelings?"(0.49) and "… to feel something, because you were feeling numb or empty?" (0.50).These data provide general support for the convergent validity of the SITBI, but it is worth noting that none of the correlations exceeded the level of 0.5.

Conclusion
The results of our study indicate that the Russian version of the ISAS-II is a valid and reliable instrument for assessing NSSI functions in a population at high risk for suicide attempts.Factor analysis of the Russian version of the ISAS-II revealed a two-factor structure (Intrapersonal and Interpersonal factors) of the instrument.The main difference between the Russian version of the instrument and the original study is that all 3 items of the subfunction "Marking distress" load more heavily on the interpersonal factor.The three most common Intrapersonal NSSI functions in patients with suicidal ideation were "Affect regulation, " "Self-punishment, " and "Anti-Suicide, " and the Interpersonal functions were "Marking distress, " "Self-care, " and "Interpersonal Influence." In people with non-psychotic mental disorders and suicidal thoughts, Interpersonal functions are associated with more severe depressive symptoms, less favorable course of NSSI and psychoticism personality traits.Validation of the ISAS-II in Russian will help to develop more accurate therapeutic strategies for people with specific motives for NSSI and will be useful for Russian mental health professionals in assessing the further course of NSSI.

TABLE 1
Sociodemographic and clinical characteristics of the sample.

TABLE 2
Factor loadings of the ISAS-II items.

TABLE 3
Prevalence of NSSI functions and internal consistency and descriptive statistics for ISAS-II domains and facet scores.

TABLE 4
Correlation analysis of NSSI functions with sociodemographic parameters, personality domains and clinical variables.Intrapersonal motive for NSSI, while communicating the level of distress and interpersonal influence were found to be the most common Intrapersonal motives.It is noteworthy that the "Self-care" motive for NSSI in the Russian version of the ISAS-II includes both Intrapersonal and Interpersonal items and cannot be completely reduced to just one of the two functions.
10.3389/fpubh.2023.1270944Frontiers in Public Health 10 frontiersin.orgcuration, Writing -original draft.SP: Investigation, Writing -original draft.IM: Writing -original draft.NV: Writing -original draft, Investigation.AnG: Formal analysis, Methodology, Writing -original draft.AY: Formal analysis, Software, Writing -original draft.AlG: Project administration, Resources, Writing -review & editing.Funding The author(s) declare financial support was received for the research, authorship, and/or publication of this article.This research was funded by grant from the Moscow Center for Healthcare Innovations [Grant No. 2412-36/22].